A known device according to DE 197 37 697 A for implementing a single-stage process has a central stationary extruder which alternately feeds two injection rotors via a two-way controlled valve. During injection molding one injection rotor is stationary while the other injection rotor is rotationally driven and transfers the preforms to a transfer carousel with cooling devices. A rotary distributor is arranged in each injection rotor which sequentially feeds the injection molds via controlled injection valves. The respective injection valve is only actuated when the injection mold has been first closed by the inner arbor, which has moved to the end position, and has been fixed.
With a device known from DE 31 24 523 A a central extruder is arranged stationary. Sequentially controlled needle valves fill the cavities of each of four injection molds which are combined, forming a unit. The injection rotor is stationary. Four rotationally driven blowing rotors are arranged on the circumference of the injection rotor. Transfer grippers grip the openings of the preforms to transfer them in groups.
With the device known from U.S. Pat. No. 3,357,046 A two extruders are provided, which operate continuously and are mounted diametrically opposite on a disk-shaped carrier. The carrier rotates about its axis until in a respective discharge position, it remains stationary in the discharge position or it is at least largely retarded before a billet emitted from the extruder is parted off and transferred to a stretch-blowing mold located stationary beneath it.
With the device known from DE 195 28 695 for realizing a single-stage process expanding arbors, which engage in the opening of the respective preform, are used for transferring the preforms manufactured by injection molding. A stationary central extruder alternately feeds two injection molds which can move to and fro along an arc-shaped guide.